Device for sharpening milled curved tooth files



Nov. 23, 1954 w. E. EDWARDS DEVICE FOR SHARPENING MILLED CURVED TOOTHFILES 2 Sheets-Sheet l Filed Aug. 5, 1953 ATTDRNEYS 2 Sheets-Sheet 2INVENTOR. 'M Wziamf'dward@ W. E. EDWARDS DEVICE FOR SHARPENING MILLEDCURVED TOOTH FILES Nov. 23, 1954 Filed Aug. 5, 1953 58 l 9 z@ 6 M695 5nited States Patent O DEVICE FOR SHARPENING MILLED CURVED TOOTH FILESWilliam E. Edwards, Gonzales, Tex.

Application August 5, 1953, Serial No. 372,527

4 Claims. (Cl. 51-96) This invention relates to abrading machines, andmore specifically, to devices for sharpening manually manipulated tools.

One of the primary objects of this invention is to provide a device forsharpening milled curved tooth files.

A further object of this invention is to provide a sharpener of the typedescribed which is non-complex in construction, inexpensive tomanufacture and to maintain, and which does not require the services ofa skilled mechanic to operate.

A still further object of this invention is to provide a Sharpener whichwill accommodate files of varying widths and thicknesses and which makesthe accommodation automatically.

Another object of this invention is to provide a stepby-step positioningmeans for the le whereby each tooth of the le is brought, successively,into proper position for the sharpening operation.

Other and further objects and advantages of this invention will becomemore apparent from a consideration of the following specification whenread in the light of the accompanying drawings, in which:

Fig. 1 is a top plan view of a le Sharpener constructed in accordancewith the teachings of this invention;

Fig. 2 isa longitudinal cross-sectional view taken on the vertical planeof line 2-2 of Fig. 1, and looking in the direction of the arrows; l

Fig. 3 is an end elevation of the Sharpener shown in Fi l;

iig. 4 is a cross-sectional View taken on the vertical plane of line4--4 of Fig. 2, and looking in the direction of the arrows;

Fig. 5 is a partial top plan view of the file holder;

Fig. 6 is a partial enlarged side elevation illustrating the engagementof the sharpening means with a tile groove; and,

Fig. 7 is a top plan view of the tile holder.

Referring now more specifically to the drawings, reference numeral 1designates, in general, a iilev Sharpener constructed in accordance withthe teachings of this invention. As shown in Figs. l, 2, 3 and 4, theSharpener 1 comprises a substantially hollow supportmember 2 having aninverted, substantially U-shaped transverse cross-section, and includinga horizontal top wall 3 having integrally formed depending spaced sidewalls 4 and 5 which terminate at their lower ends in integrally formed,opposed, and outwardly turned flanges 6 and 7, respectively. The sidewalls 4, 5 and their respective flanges 6, 7 are inclined at an anglewith respect to each other and converge toward the open front end 8 ofthe support member 2. Referring to Fig. 1 of the drawings, it is seenthe rear end 9 of the top wall 3 is arcuate in configuration and thatthe support member 2 is symmetrical in and about its longitudinal axis.

The anges 6, 7 are transversely apertured to receive therethrough aplurality of screws or bolts 10 whereby the member 2 may be rigidly anddetachably secured to a suitable base 11 with the top Wall 3 in elevatedspaced relation with respect thereto.

As seen in Figs. 1, 2 and 3, the top wall 3 is slotted at 12 to receivetherethrough a grinding wheel 13 mounted on the drive shaft 14 of anelectric motor 15. The motor 15 is provided with a substantiallycircular split casing 17 having a pair of opposed substantially parallelflanges 18. The casing 17 is tightly clamped around the motor 15 bymeans of the bolt 19 and wing nut 20 which engage the exterior sides ofthe flanges 18.

2,694,882 Patented Nov. 23, 1954 ice Ihe casing 17 is also provided witha pair of opposed (dla'metrlcally) bolts 21 which extend radially fromopposlte sides of the casing for reception within the arcuately shaped,oppositely disposed, spaced and substantlally parallel slots 22 formedin the opposed, spaced and parallel bracket members 23. Wing nuts 24co-op erate with bolts 21 to lock the casing 17 and the motor 15 inadjusted position relative to the bracket members 23.

The bracketV members 23 have integrally formed laterally extendingflanges 25 at the lower ends thereof which are apertured to receive thescrews or bolts 26 therethrough for detachable securement to the upperwall 3. As seen in the drawings, the brackets 23 support a hanger 27 attheir respective forward and upper corners, the hanger 27 beingapertured to receive therethrough the shank of an eyebolt 28. Theslotted portion 29 of the eyebolt 28 is disposed between the flanges 18and is adapted to receive a cross-pin 30 supported thereby. Lock andwing nuts 31 and 32, respectively, are mounted on the threaded shank ofthe eyebolt 28 and lock against opposed sides of the hanger 27 inadjusted positions.

The motor 15 is energized through the cable 33 which is connected with asuitable source of E. M. F.

The tile holder is designated, in general, by the reference numeral 34,and comprises an elongated channel member 35 having a substantiallyinverted U-shaped transverse cross-section including a top wall 36, apair of opposed spaced and parallel side walls 37 depending therefromand terminating at their respective lower ends in outwardly turnedoppositely disposed anges 38. Each of the flanges 38 has a plurality oftransverse apertures formed therein to receive bolts 39 which serve tosecure an elongated bed plate 40 to the channel member 35, the bed plate40 extending across the open lower end of the channel member 35substantially throughout its length.

A plurality of laterally spaced elongated leaf springs 41 have one oftheir respective ends rigidly secured to the bed plate 4l) while theother ends thereof engage against an elongated bottom spacer plate 42which extends longitudinally of and parallel to the bed plate 40. Asseen in Fig. 2, the opposed ends of the spacer plate 42 are bentdownwardly at 43 and inwardly toward each other at 44 to surround theopposite ends of the bed plate 40 and constitute means for limiting themovement of the spacer plate 42 towards the top Wall 36.

The top wall 36 is punched outwardly to form a dome 44 provided with acentral aperture aligned with an aperture formed in the top wall 3 ofthe support member 2. The support member 2 and the iile holder 34 arepivotally connected together by a bolt 45 which passes through thelsigned apertures and is secured in position by the nut An elongatedpawl 47 extends longitudinally of the top wall 36 and has one of itsends xedly secured thereto by the screw 48, While the other end thereofprojects through an opening 49 formed in the dome 44 and terminates atsubstantially the axis of rotation of the holder 34. As seen in Figs. 2,5 and 7, the top wall 36 of the file holder 34 is slotted at 5t) forregistery with the slot 12 formed in the top Wall 3 of the supportmember 2.

A second pawl 51 has one of its ends xedly secured to the top wall 36,adjacent its rear end, by the screw 52, while the other end of the pawlextends downwardly through a slot 53 formed in the top wall 36.

As seen in Figs. 4 and 5, a plurality of leaf springs 54 have one oftheir respective ends iixedly secured to a side 37 of the tile holder 34while the other ends thereof bear against a second spacer plate 55 whichextends lon gitudinally of the le holder. This spacer plate is at rightangles to and bears against the spacer plate 42 and tile 62. Verticaldisplacement of the spacer plate 55 is prevented by the top wall 36 andthe bed plate 40 on which it is supported for lateral movement.

Longitudinal displacement of the spacer plate 55 is prevented byproviding oppositely disposed lateral extensions 56 which are reverselybent at 57 to loosely surround the ends of the side wall 37.

A guide and spacer block 58 is secured on the top wall 36 adjacent therear end thereof and is provided with a groove 59 to slidably receivethe rear marginal end of the top` wall' 3: A keeper Vplate-'60issupported on the block 58 with a side thereof in overlapping relationwith respect to the rear marginal edge of the top wall 3. Block 58 andthe keeper plate 60 are rigidly secured to the top wall 36 ofthe fileholder 34 by means of abolt 61.

In operation, a file 62 is inserted lengthwise between the top wall 36and the spacer platev 42, making engagement with first pawl 51 untilfirst tooth is positioned under grinding wheel 13 and' then pawl 47. Theabrading wheel. 13 is brought into adjusted contact with the le teeththrough the openings 12 and 50 by adjustment of the motor 15. This isaccomplished by varying the position of the bolts 21 relative to theslots 22 and by changing the relative positions of the cross-pin 30 andthe hanger 27 through the bolt 28- and the nuts 31 and 32. TheA motor 15is then energized through the cable 33, and the operator then` swingsthe le in arcs indicated by the arrows in Fig. l.

As each tooth is sharpened, the operator advances they file one toothforward and repeats the swinging operation of the tile after firstpulling backwardly thereon to make certain that the pawls have lockedwith the le teeth.

As the sharpening progresses the front end of the le becomessubstantially enclosed by the le holder, and at that time the operatorwill utilize the le holder 34 and the guide and spacer block 58 or therear end of the le as a handle to effect the arcuate movement..

It is deemed obvious that from the construction recited above, thespacer plates 42 and 55 enable the holder 34" to accommodate files ofappreciable widths and thicknesses and will maintain the same insharpening position under the influence of the leaf springs 41 and 54.

The invention described above, while'having general application, isespecially valuable to mechanics engaged in automobile body and fenderrepairs. To such mechanics, a sharp file having seven to eight teeth perinch is a mostimportant tool. To sharpen such tiles it is important andcritical that the pawl 47have its tile engaging end at the pivot pointor axis of the holder, or at one inch or added equal increments f oneinch. therefrom. Additionally, in grinding tiles having seven or eight.teeth per inch, the grinding. wheel must be adjusted to engage that tiletooth which is two inches l(2") from the tooth falling directlypunderthe axis of rotation of the holder. For example the arcuate curvature oftiles having seven or eight teeth per inch will be found to be struckfrom a radius of two inches. Thus, in the described embodiment, eitherle could'be sharpened by positioning the grinding wheel for engagementwith the fourteenthy or sixteenth teeth thereof, or by measurementV thegrinding wheel could be spaced from the axis of rotation at two inches.

The hanger 27 is fixed in any suitable manner tothe bracket members 23.

Having described andV illustrated this invention in detail, it is to beunderstood that theI embodiment herein disclosed lis offered merely byway of example, and `that' the invention is to be limited onlyby thescope yof the following claims.

Irclaim:

l. A tile sharpening device comprising asupport member having a pair ofspaced sides disposed at an angle to each other and a wall secured toand bridging said sides, an elongated channel shaped member comprising ale holder, said member having an end thereof pivotally connected to saidwall on oneside thereof, said wall and said channel member each havingopenings formed therein in register with each other, a pair of bracketsmountedl on thefotherv side' of said wall'and projecting therefrom, anda motor driven grinding wheel adjustably supported on said brackets,said grinding wheel being adapted for insertion through said openingsfor engagement with a tooth of a file disposed within said holder.

2. A tile sharpening device comprising a support member having a pair ofspaced sides disposed at an angle to each otherland azwall secured toand bridging said sides, said wall having an opening formedl therein, apair of spaced substantially parallel brackets secured to one side ofsaid wall and extending laterally therefrom, each of said bracketshaving an arcuate slot formed therein, a substantially cylindricalcasing disposed between said brackets, said casing having meansconnected therewith for insertion within said slots for adjustment ofsaid casing relative to said slots, an electric motor embraced andsupported by said casing, a grinding wheel operatively connected withsaid motor, an elongated channel memberA havingv an end thereofpivotally secured to said wall on the other side thereof and having anopening therein in registry with said opening formed in said wall, theother end of saidchannely member beingfree to oscillate between saidside walls, and said grinding wheel being adapted for insertion throughsaid openings for engagement with a tooth of a tile disposed within saidchannel member.

3. A le sharpening device as defined in claim 2, and said channel memberhaving resilient means associated therewith to accommodate tiles havingvarying widths andthicknesses.

4. A file sharpening device comprising a support member having a pair ofkspaced sides disposed at an angle to eachother and a wall secured toand bridging said sides, said wall having an opening formed therein, apair of spaced substantially parallel brackets secured to one sideofsaid wall and extending laterally therefrom, each of said bracingbrackets having an arcuate slotl formed therein, a. casing for anelectric motor adjustably supporting one end of an electric motor withinsaid slots, adjustable means associated with said casing for securingsaid casing in adjusted relation relative to said slots, a grindingwheel connected with said motor, an elongated channel shaped memberhaving an. end thereof pivotally connected with said wall and having anopening formed therein for registry with saidtopening formed in saidwall, a spacer plate mounted within said channelr member substantialyparallel to said'wall, resilient means mounted within said channelvmember constantly urging said plate towards said wall, a second spacerplate mounted within said channel member, resilient meansfor urgingconstantly said last named plate at right angles toward` the movement ofsaid' rst platey under. the influence of said tirst resilient means, andsaid channel mem.- ber having an opening formed therein in registry withsaid first named opening to receive. said grinding. wheel therethrough..

References Cited in the le of this patent. UNI-TED STATES PATENTS NumberName Date 1,777,135 Bailey Sept. 30, 1930 2,096,890 Ferrel Oct. 26,1.937 2,212,999' Faulder Aug. 27,` 1940 2,222,034 Jackson Nov. 19, 19402,367,850 Dusevoir Jan. 23, 1945 2,430,984 Hopkins Nov. 18, 19472,528,511 Graham et al. Nov. 7, 1950 2,627,143 Beyer Feb. 3, 1953

